<span>
  @text
  &nbsp;
  <Cascader Options="@options" SelectedNodesChanged="OnChange">
    <a >Change city</a>
  </Cascader>
</span>

@code {
    string text = "Unselect";
    
    void OnChange(CascaderNode[] selectedNodes)
    {
        text = string.Join(", ", selectedNodes.Select(x => x.Value));
    }

    List<CascaderNode> options = new List<CascaderNode>() 
    {
      new()
      {
          Value = "zhejiang",
          Label = "Zhejiang",
          Children = new CascaderNode[]
          {
              new()
              {
                  Value = "hangzhou",
                  Label = "Hangzhou",
                  Children = new CascaderNode[]
                  {
                      new()
                      {
                          Value = "xihu",
                          Label = "West Lake",
                      },
                  }
              },
          },
      },
      new()
      {
          Value = "jiangsu",
          Label = "Jiangsu",
          Children = new CascaderNode[]
          {
              new()
              {
                  Value = "nanjing",
                  Label = "Nanjing",
                  Children = new CascaderNode[]
                  {
                      new()
                      {
                          Value = "zhonghuamen",
                          Label = "Zhong Hua Men",
                      },
                  }
              },
          },
      }
    };
}